Eyes

immune privilege

the evolution of the vertebrate eye has favored reduced innate immunity, macrophages aren’t needed on the surface to defend from bacteria

conjunctiva

thin tissue that secretes oil and mucus containing fluid that lubricates and protects the eye surface

cornea

5-6 layers of epithelial cells that act as the windshield of the eye

lacrimal gland

gland that produces tears

nasolacrimal duct

duct that collects tears

tear composition

lactoferrin that starves bacteria, lysozymes that break down peptidoglycan

common organisms in eye microflora

corynebacterium (main), also common skin staphylococci, streptococci, neisseria (not gonorrhea)

adult conjunctivitis causes

microbes, contact contamination, eye injury, traumatic event

conjunctivitis with milky discharge

bacterial infection

conjunctivitis with clear, watery exudate

viral infection

neonatal conjunctivitis causes

gonorrhea, chlamydia, herpes from mother’s vagina

keratitis

invasion of deeper eye tissues, can cause complete corneal destruction

keratitis causes

herpes simplex 2, acanthamoeba from dirty water/contacts